Defendant
1 case as defendant.
D&M Holdings Inc., which operated as The D+M Group, was a manufacturer and distributor of premium consumer electronics. The company was formed in 2002 through the merger of high-end audio brands Denon and Marantz. Over the years, its portfolio grew to include other well-known audio brands such as Boston Acoustics. After a period of ownership by private equity firm Bain Capital, D&M Holdings was acquired by Sound United LLC in February 2017. The combined company, known as Sound United, continued to operate the distinct brands. Sound United and its portfolio, including the former D+M brands, were later acquired by HARMAN International, a subsidiary of Samsung, in a deal announced in 2025.
The D+M Group was an operating company that designed, manufactured, and sold a wide range of audio and video equipment. Its core product lines consisted of home theater systems, A/V receivers, amplifiers, CD players, speakers, and wireless multi-room audio systems. The company was known for its premium brands, particularly Denon, a broad-market audio equipment manufacturer, and Marantz, which focused on the high-fidelity (hi-fi) market. Its products were sold globally through a network of retailers and custom installers.
Based on the provided data, D&M Holdings has the patent-litigation posture of an operating company defending its products in court. The company is listed as a defendant in its single tracked case and has no record of initiating patent litigation as a plaintiff. This pattern is typical for a manufacturer of consumer goods that is targeted by a competitor over product features. The lawsuit was filed in the U.S. District Court for the District of Delaware, a common venue for patent disputes.
The company's most notable litigation is the tracked case, Sonos, Inc. v. D&M Holdings Inc. d/b/a THE D+M GROUP, filed in 2014. This patent infringement lawsuit was brought by competitor Sonos, a pioneer in the wireless multi-room audio market. The suit alleged that D&M's HEOS by Denon line of wireless audio products infringed on several Sonos patents. The case involved extensive legal maneuvering, including counterclaims filed by D&M, and proceeded for several years.
The case was terminated following a confidential settlement agreement between the parties, and the dismissal was filed with prejudice. During the proceedings, patent 7,571,014 was subject to a claim construction ruling.